Well, I'm impressed!

[wco81]

But even if it has a 3D model or map, how would it know where that 3D map is?

I guess since it had GPS until it entered the tunnel or entrance to the garage?

It did move slowly through the tunnel so while it avoids crashes, it would be vulnerable to passerbys taking a bat to it or something,

 

[JoelP]

The only way that cars navigated before GPS was dead reckoning. Is this done with dead reckoning? If so it cannot be anywhere near as accurate as GPS guidance.